It actually looks quite simple, but technically it is a small stroke of genius: SpearUAV in Israel has solved the problem of a miniature flying drone that can be used underwater and perform reconnaissance over water - it is called the "Ninox 103 UW Sub-to-Air". The Israeli company from Tel Aviv presented the autonomous "Ninox" to the public at Undersea Defence Technology in Rotterdam.
Ninox 103 small drone in a container. Graphic: (spearuav.com)
It is actually just a folded quadcopter with a camera and data transmission module, which is ejected as a can from a submerged submarine, shot out of the vertical container after breaking through the water surface, unfolds at a safe height and starts its mission supported by intelligent programme control. It can remain in the container on the water surface for 24 hours and, once launched, fly 10 kilometres autonomously (under control if necessary) for 45 minutes.
Ninox 103 small drone in flight. Graphic: (spearuav.com)
With a payload capacity of one kilogramme, a wide range of miniaturised sensors can be integrated and communicate with any receivers in the air, on land, on or under the sea. Provides the submerged submarine commander with a flying periscope!
Click here to take a look: https://youtu.be/LcAdhRNqCQU
English 
German
A further idea deri from the planned VOLANS Module of TRIPLE M System developed by comp. GABLER Maschinenbau...